Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Difficult to treat Crohn's disease (DTT-CD) was defined by the International Organization for the Study of Inflammatory Bowel Diseases (IOIBD) in 2023, which refers to CD patients with poor response to drug treatment and poor prognosis. Foreign epidemiological studies have shown that DTT-CD accounts for 24.8% of all CD patients, and most of them are patients with advanced treatment failure according to more than two different mechanisms. Our previous retrospective data suggested that compared with foreign DTT-CD patients, there was no significant difference in the proportion of patients with advanced treatment failure due to more than two different mechanisms, but the proportion of patients with recurrence after two intestinal resection and complex anal fistula was increased. Therefore, this project aims to determine the current prevalence and epidemiological status of DTT-CD in China; To clarify the difference in efficacy and prognosis between DTT-CD patients and non DTT-CD patients using advanced treatment (including biological agents and small molecule drugs); Objective to evaluate the incidence and risk factors of non DTT-CD patients progressing to DTT-CD within 1 year. To further verify whether the domestic DTT-CD population is significantly different from the foreign population, and provide theoretical support for the selection of subsequent treatment options.
Not provided
Not provided
Not provided
Not provided
Not provided
| Label | Type | Description | Intervention Names |
|---|---|---|---|
| Total study population | The total study population included all CD patients who visited the Sixth Affiliated Hospital of Sun Yat sen University during the specified time period (November 2025 to January 2026), including newly diagnosed and previously diagnosed patients |
Not provided
| Measure | Description | Time Frame |
|---|---|---|
| steroid-free remission | Compare the steroid-free clinical remission rates of patients with DTT-CD and non DTT-CD during the induction and maintenance periods in the patients using biologics or small molecule drugs. "Steroid-free" refers to patients who do not receive concomitant steroid medication. | From the beginning of enrollment to 1 year |
| Measure | Description | Time Frame |
|---|---|---|
| Epidemiological status of Difficult-To-Treat Crohn's Disease | Calculate the proportion of DTT-CD patients in the total population | From the beginning of enrollment to three months later |
| Clinical reponse rate |
Not provided
Inclusion Criteria:
Exclusion Criteria:
Not provided
Not provided
Patients with Crohn's disease who visited tertiary hospitals, including those newly diagnosed and those previously diagnosed.
| Name | Role | Phone | Extension | |
|---|---|---|---|---|
| Xiang Gao | Contact | +86-020-38663423 | gxiang@mail.sysu.edu.cn |
Not provided
| Facility | Status | City | State | ZIP | Country | Contacts |
|---|---|---|---|---|---|---|
| Sixth Affiliated Hospital, Sun Yat-sen University | Recruiting | Guangzhou | Guangdong | 510655 | China |
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
| ID | Term |
|---|---|
| D003424 | Crohn Disease |
| ID | Term |
|---|---|
| D015212 | Inflammatory Bowel Diseases |
| D005759 | Gastroenteritis |
| D005767 | Gastrointestinal Diseases |
| D004066 | Digestive System Diseases |
Not provided
Not provided
Not provided
Not provided
Not provided
Compare the clinical response rates of patients with DTT-CD and non DTT-CD during the induction and maintenance periods in the patients using biologics or small molecule drugs.
| From the begining of enrollment to 1 year. |
| Clinical remission rate | Compare the clinical remission rates of patients with DTT-CD and non DTT-CD during the induction and maintenance periods in the patients using biologics or small molecule drugs. | From the begining of enrollment to 1 year |
| Endoscopic outcome | Compare the endoscopic outcomes of patients with DTT-CD and non DTT-CD during the induction and maintenance periods, including the endoscopic response rate, the endoscopic remission rate, and the mucusal healing rate in the patients using biologics or small molecule drugs. | From the begining of enrollment to 1 year |
| Ultrasound outcome | Compare the ultrasound outcomes of patients with DTT-CD and non DTT-CD during the induction and maintenance periods in the patients using biologics or small molecule drugs, including the transmural response rate and the transmural remission rate. | From the begining of enrollment to 1 year |
| Postoperative recurrence rate | Compare the postoperative recurrence rates of DTT-CD and non DTT-CD: postoperative recurrence is defined as the recurrence of clinical symptoms, or endoscopic mucosal ulcers, or imaging evidence of intestinal inflammation, etc. | From the begining of enrollment to 1 year |
| Safety differences | Compare the safety differences between DTT-CD and non-DTT-CD after one year of biologic therapy. | From the begining of enrollment to 1 year |
| D007410 | Intestinal Diseases |